Tube bender

ABSTRACT

A portable tube bending device having a base member and a first die member which has at least one tube receiving die recess therein and which is mounted for longitudinal movement along its axis during a tube bending operation. A handle is connected to a second die member which has a curved surface and a tube receiving recess in the curved surface therein and is adapted to cooperate with the first die member by being pivotable with respect thereto. A tube gripping device is secured to the second die member and engages a portion of the tube spaced longitudinally along the axis of the tube from the location where the first and second die members engage one another to facilitate a bending of the tube when the handle is moved relative to the base member. The tube gripping device is secured to the second die member by an elongated chain so that the tube gripping device will always remain connected with the pivotal die member. A notch is provided in the second die member and is adapted to receive a tube fitting therein to facilitate a bending of tubes having the fittings premounted thereon.

United States Patent [191 Okamuro June 25, 1974 [22] Filed:

[ TUBE BENDER [75] Inventor: James A. Okamuro, Kalamazoo,

Mich.

[73] Assignee: Burroughs Tool & Equipment Corporation, Kalamazoo, Mich.

Apr. 23, 1973 21 Appl. No.: 353,582

Primary Examiner-Charles W. Lanham Assistant Examiner-Robert M. Rogers Attorney, Agent, or Firm-Woodhams, Blanchard & Flynn [5 7] ABSTRACT A portable tube bending device having a base member and a first die member which has at least one tube receiving die recess therein and which is mounted for longitudinal movement along its axis during a tube bending operation. A handle is connected to a second die member which has a curved surface and a tube receiving recess in the curved surface therein and is adapted to cooperate with the first die member by being pivotable with respect thereto. A tube gripping device is secured to the second die member and engages a portion of the tube spaced longitudinally along the axis of the tube from the location where the first and second die members engage one another to facilitate a bending of the tube when the handle is moved relative to the base member. The tube gripping device is secured to the second die member by an elongated chain so that the tube gripping device will always remain connected with the pivotal die member. A notch is provided in the second die member and is adapted to receive a tube fitting therein to facilitate a bending of tubes having the fittings premounted thereon.

10 Claims, 7 Drawing Figures PAIENTEDJUNZSIQM SHEET 1 0F 2 I lsT TUBE BENDER FIELD OF THE INVENTION This invention relates to a tube bending device and, more particularly, relates to a tube bending device of the small and portable type wherein the die members are interchangeable to facilitate the bending of different diameter tubes.

BACKGROUND OF THE INVENTION Many large size and automated tube bending devices are known and are presently being utilized in the field. Further, tube bending devices wherein the die members are interchangeable to facilitate a bending of tubes having'different diameters are also known but a small, manually operable tube bending device for use in bending particularly small diameter tubes in the range of inch in diameter up to approximately inch in diameter have not been entirely satisfactory.

The particular field in which the invention arose was in the utilization of tubing in present day automobile carburetors and hydraulic brake lines. Heretofore, the automobile manufacturer manufactured carburetor repair kits and brake line kits having tubing prebent to shape thereby forcing the automobile mechanic to stock a number of different carburetor repair kits, each having differently sized and differently bent tubes to permit the mechanic to make a rapid repair. However, the automobile manufacturer has ceased to manufacture the repair kits. Since equipment available for use by automobile mechanics for permitting the bending of different diameter tubes is not generally satisfactory for use in garages and the like by unskilled technicians at tube bending, it is a desire of the present invention to provide apparatus which will permit a tube bending operation by generally unskilled technicians and yet facilitate the repair of automobile engines and brake lines by permitting the automobile mechanic to bend different diameter tubes close to the mechanics work station.

Although this invention arose out of a need for equipment for use by automobile mechanics, it is to be recognized that the device disclosed herein is capable of use in other work environments requiring tube bending operations.

Accordingly, it is a primary object of this invention to provide apparatus to facilitate a tube bending operation closely adjacent a work environment which requires that a tube bending operation be carried out.

It is another object of this invention to provide apparatus to facilitate a tube bending operation of tubes having flared ends thereon and the fitting nuts being premounted between the flared ends of the tubes.

It is another object of this invention to provide apparatus which utilizes interchangeable die parts to facilitate the bending of different diameter tubes.

It is a further object of this invention to provide interchangeable die parts which are easily identifiable as being part of a set of parts adapted to handle a different diameter tubing and rendering the interchangeability of the die parts simple to thereby facilitate a speedy and convenient use of the tube bending device.

It is a further object of this invention to provide a tube bending device which is small and compact in size and yet providing sufficient leverage to facilitate the 2 bending of tubing in the range of '74: inch up to a diameter of 1% inch.

It is a further object of this invention to mount at least one of the interchangeable die parts on one of the pair of relatively pivotable members to minimize the number of loose interchangeable die parts.

It is a further object of this invention to provide two separate sets of cooperable interchangeable dies, wherein one interchangeable die part is nonremovably connected to one of the relatively pivotable parts of the tube bending device and the other die part comprises two separate parts which are connected by an elongated flexible element so that the separate parts will always remain connected together even though not a permanently connected part of the tube bending device.

Other objects and purposes of this invention will be apparent to persons acquainted with tube bending apparatus of this general type upon reading the following specification and inspecting the accompanying draw ings, in which:

FIG. 1 is a side elevational view of a tube bending device embodying the invention;

FIG. 2 is an end elevation view of the tube bending device taken along the line II-II of FIG. 1;

FIG. 3 is a sectional view taken along the line III-III of FIG. 1;

FIG. 4 is an end view of the tube bending device taken along the line IV-IV of FIG. 1;

FIG. 5 is a side elevational view of the tube bending device similar to FIG. 1 wherein the position of the tube gripping element is altered;

FIG. 6 is a sectional view of the embodiment illustrated in FIG. 5 and corresponds to a section taken along a line VIVI in FIG. 3; and

FIG. 7 is a sectional view corresponding to a section taken along the line VIVI in FIG. 3 except that the pivotal die part has been pivoted from the FIG. 6 position to the FIG. 7 position.

Certain terminology will be used in the following description for convenience in reference only and will not be limiting. The words up," down, right" and left" will designate directions in the drawings to which reference is made. The words in and out will refer to directions toward and away from, respectively, the geometric center of the device and designated parts thereof. Such terminology will include the words above specifically mentioned, derivatives thereof, and words of similar import.

DETAILED DESCRIPTION A tube bending device 10 is illustrated in FIG. 1 and has a base member 11 bent as at 12 to generally define an L-shape. One leg 13 of the L-shaped based member defines a handle and the shorter leg portion 14 has a bifurcate end portion 16 defined by a pair of laterally spaced ears l7 and 18. A space or gap 19 is defined between the pair of ears l7 and 18 and, more specifically, by a pair of opposed and parallel surfaces 21 and 22 on the inwardly facing sides of the ears l7 and 18, respectively. A surface 23 extending generally at a right angle to the surfaces 21 and 22 defines the bottom or left hand end of the gap 19 in the base member 1 1. A pair of axially aligned openings 24 and 26 are provided in each of the ears l7 and 18, respectively, adjacent the free ends thereof. An opening 27 is provided in the leg 14 and extends generally parallel through the leg 14 parallel to the surface 23.

An elongated die member 28 having plural side faces, here four side faces 31, 32, 33 and 34 is mounted in the gap 19 between the ears 17 and 18. The side faces 31, 32 and 33 of the die member slidingly engage the surfaces 22, 23 and 21, respectively. Each of the side faces of the die member have an elongated and straight tube receiving recess therein, the diameter of each tube receiving recess being different from the other tube receiving recesses. More specifically, the surface 31 has a tube receiving recess 36 therein which is less in diameter than the tube receiving recess 37 in the side face 32 as well as the tube receiving recess 38 in the side face 33. A tube T is shown received in a tube receiving recess 39 in the side face 34. An opening 41 (FIG. 6) is provided through the longitudinal center of the die member 28. A generally C-shaped wire member 42 is provided, the body of which is received in the opening 27 and the legs 43 and 44 of which are bent adjacent the free ends 46 and 47 and received in the outwardly opening ends of the opening 41. Thus, a longitudinal sliding movement of the die member 28 parallel to its longitudinal axis is possible and will be limited by an engagement of the legs 43 and 44 with the opposite side surfaces of the legs 14 of the base member 11.

The corners on the elongated die member 28 adjacent one end are rounded as at 48, 49, 50 and 51 as illustrated in FIGS. 1 and 4. Thus, a sliding of the elongated die member 28 until the leg 43 of the wire member 42 engages the upper surface of the leg 14 of the base member 11 will position the rounded comers 48, 49, 50 and 51 between the surfaces 21 and 22 in the gap 19. The diameter of the cylinder formed by the aforesaid rounded edges 48, 49, 50 and 51 is less than the spacing between the surfaces 21 and 22 and since the opening 41 through the longitudinal center of the elongated die member 28 is positioned equal distance from the surfaces 21, 22 and 23 in the gap 19, it will be possible to rotate the elongated die member 28 to permit a positioning of one of the four tube receiving recesses at a location remote from the surface 23 such as the position of the illustrated tube receiving recess 39.

A second die member 56 is positionable between the ears 17 and 18 and has an opening 57 (FIG. 3) therethrough which is alignable with the axially aligned openings 24 and 26 in the ears 17 and 18, respectively. A pin 58 is removably received in the axially aligned openings 24, 26 and 57 as illustrated in FIG. 3 and serves to render the die member 56 pivotable about the axis of the pin 58. An enlarged knob 59 is provided on one end of the pin 58 to facilitate an easier handling of the pin 58.

A curved surface 61 is provided on the die member 56, the radius of which is concentric with the axis of the pin 58. The curved surface 61 is adapted to engage the surface 34 of the die member 28. A tube receiving recess 62 is provided in the curved surface 61 and is aligned with the tube receiving recess in the die member 28. The diameter of the tube receiving recess 62 corresponds to the diameter of the tube receiving recess 39 in the die member 28 so that the combined diameter of the tube receiving recesses 39 and 62 equals the outside diameter of the tube T in which a bend is to be formed.

A receptacle 63 is provided in the die member 56 remote from the curved surface 61 and receives an elongated handle 64 therein to facilitate a pivoting of the die member 56 about the axis defined by the pin 58. The handle 64 is preferably releasably received in the receptacle 63.

A notch 76 is cut into the die member 56 and opens outwardly toward the tube T when the die member 56 is pivotally secured to the base 11. The notch 76 is of a sufficient depth to receive a fitting nut 77 premounted on the tube T as illustrated in FIGS. 6 and 7. It is a customary practice to bend tubing of predetermined lengths with a flared end being provided on the opposite ends thereof. This necessitates the mounting of the fitting nuts 77 on the tube prior to the flaring operation. The flared end 78 shown in FIGS. 6 and 7 is a double flared end due to the bending of the endmost portion of the tube back on itself. The double flared end is a requirement on tubing used in most vehicles and is most difficult to make without the requirement of special machinery. Thus, tubing having the double flared ends on opposite ends is purchasable in a multitude of straight lengths and all that the mechanic is required to do is to estimate the length of the tubing for a given job and then obtain the correct length. It is no longer necessary, therefore, for the mechanic to stock a multitude of prebent tubes.

A pin 66 extends outwardly from the die member 56 in a direction parallel to the axis of the opening defined by the tube receiving recesses 39 and 62 at the location where the curved surface 61 engages the surface 34 of the die member 28. A tube gripping member 67 has an opening 68 therein which is adapted to receive the pin 66 as illustrated, for example, in FIGS. 6 and 7. A recess 69 is provided in the tube gripping member 67 and opens outwardly to an edge thereof. The bottom of the recess 69 is spaced from the opening 68 a distance which is equal to the spacing between the opening 68 and the theoretical line defined by the axis 70 of the tube receiving recesses 39 and 62 at the location where the curved surface 61 engages the surface 34 on the die member 28 and the radius of the tube T.

A pin 71 is provided on the tube gripping member 67 and the axis thereof is spaced from the opening 68 a distance generally equal to the spacing of the axis 70 and the axis of the opening 68. In other words, when the tube gripping member 67 is positioned so that the pin 66 on the die member 56 is received in the opening 68, the axis of the pin 71 will be aligned with the axis 70 defined by the tube receiving recesses 39 and 62 as illustrated in FIG. 6 and received in the free end of the tube T. An elongated flexible member, such as a chain 72, is secured by any convenient means, as by a screw 73 or the like, to both the tube gripping member 67 and the die member 56. The purpose of this connection is to assure that the size of the recess 69 and pin 71 on the tube gripping member 67 will correspond to the size or diameter of the tube receiving recess 62 in the die member 56. That is, the diameter of the pin 71 is of a size to be received into the center of a tube T having a diameter which corresponds to the diameter formed by the tube receiving recesses 39 and 62. Similarly, the recess 69 is adapted to receive a tube having an outer diameter equalling the diameter of the tube receiving recesses 39 and 62.

OPERATION Although the operation of the device embodying the invention will be obvious to skilled persons, a brief summary thereof will be given for convenience.

Prior to a tube bending operation, one of the tube receiving recesses 36, 37, 38 or 39 is positioned to face outwardly of the gap 19 between the ears l7 and 18 of the base member 11. For purposes of discussion, the illustrated tube receiving recess 39 will be used. A die member 56 is selected by the operator. The operator must choose a die member 56 having a tube receiving recess 62 therein which is equal to the diameter of the selected tube receiving recess 39 in the die member 28. The die member 56 is then positioned so that the opening 57 therein is rendered coaxial with the aligned openings 24 and 26 in the ears l7 and 18, respectively, and the pin 58 is then inserted therethrough to render the die member 56 pivotal with respect to the base member 11.

A tube T is then placed on the elongated die member 28 and in the tube receiving recess 39 and slid between the die members 28 and 56 to a position generally corresponding to that illustrated in FIG. 1. At this time, the tube gripping member 67 is mounted onto the die member 56 by placing the pin 66 thereon into the opening68 in the tube gripping member 67. The recess 69 receives the tube T therein as is illustrated in FIG. 2. As a result, a pivoting motion of the die member 56 from the solid line position in FIG. I to the broken line position will effect a bending of the tube to a desired angle. Generally, the limits of the angle are in the range of 0 to 90 with the embodiment illustrated in FIG. 1.

When the very end portion of the tube T is to be bent to form a desired angle, the tube gripping member 67 is positioned as illustrated in FIG. 5, for example. More specifically, the pin 71 thereon is positioned to be aligned with the axis 70 defined by the diameter of the tube receiving recesses 39 and 62 at the location where the curved surface 61 on the die member 66 engages the surface 34 on the elongated die member 28. The end of the tube T is slid over the pin 71 until the tube gripping member 67 abuts the die member 56 as illustrated in solid lines in FlG. 5. Thereafter, the die member 56 may be pivoted, using the handle 64, relative to the base member 11 and the pin 71 will serve to effect a bending of the tube T to a desired angle.

it is to be noted that during the bending motion, the elongated die member 28 is permitted to move longitudinally along its axis to facilitate a movement of the tube T during the bending process.

When the tube T has a fitting nut 77 thereon and the very end portion of the tube adjacent the fitting is to be bent, the fitting nut 77 is positioned in the notch 76 in the die member 56 as illustrated in FIGS. 6 and 7. The pin 71 on the tube gripping member 67 is thereafter slid into the open end of the tube T as illustrated in FIG. 6. Thereafter, a tube bending operation may take place to bend the tube T to a desired angle.

Since the die member 56 can be removed from the base member 11, the chain 72 securing the tube gripping member 67 to the die member 56 will always assure that the size of the recess 69 and pin 71 on the tube gripping member 67 corresponds to the diameter of the tube receiving recess 62 in the die member 56. Generally, a set of die members 56 will be provided, the number of which equals the number of tube receiving recesses in the elongated die member 28. However, for

. 6 purposes of illustration, only one such die member 56 is illustrated in the drawings, it being understood that the remaining die members are identical to the illustrated die member 56 except that the diameter of the tube receiving recesses 62 therein are different for each of the other die members 56. Each of the other die members 56 also has a receptacle 63 therein adapted to receive the illustrated handle 64. Since the handle 64 is releasably received in the receptacle 63, the handle 64 can also be utilized with each of the other die members 56.

Although a particular preferred embodiment of the invention has been disclosed in detail for illustrative purposes, it will be recognized that variations or modifications of the disclosed apparatus, including the rearrangement of parts, lie within the scope of the present invention.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A portable tube bending device, comprising:

a base member having a bifurcate end portion defined by a pair of coextensive and laterally spaced ears;

an elongated first die member having a first tube receiving recess therein extending parallel to the longitudinal axis thereof and having a diameter equal to the diameter of a tube;

mounting means for mounting said first die member on said base member in said space between said ears and adapted to support said first die member for reciprocable movement longitudinally of the longitudinal axis of said die member through said space relative to said base member;

a second die member having a curved surface thereon and a second tube receiving recess in said curved surface equal in diameter to said first tube receiving recess, said second die member having first coupling means thereon;

pivot support means for pivotally supporting said second die member for movement between said ears, said second die member having a curved surface the radius of which is generally equal to the spacing between said pivot support means and said first die member;

means defining an elongated handle and releasable securing means for securing said handle to said second die members;

tube gripping means having second coupling means thereon cooperable with said first coupling means to secure said tube gripping means to said second die member;

attaching means on said tube gripping means for engaging said tube at a location spaced longitudinally along the axis thereof from the location where said first and second die members engage said tube, said attaching means being adapted to cooperate with a tube having a diameter corresponding to the diameter of said second tube receiving recess whereby a pivoting of said second die member about said pivot support means will effect a bending of a portion of said tube engaged by said tube gripping means relative to a portion of said tube located in said first and second tube receiving recesses; and

elongated flexible connecting means having a finite length for connecting said tube gripping means to said second die member so that said second die member and said tube gripping means will remain attached even though said first and second coupling means become uncoupled.

2. A portable tube bending device according to claim 1, wherein said elongated flexible connecting means is of sufflcient length to facilitate a manipulation of said tube gripping means relative to said second die memher.

3. A portable tube bending device according to claim 1, wherein said attaching means on said tube gripping means comprises an elongated pin and means defining a recess therein, both said pin and said recess being positioned to engage a portion of said tube located in said first and second tube receiving recesses whereby a pivoting of said second die member relative to said base member will effect a bending of said tube.

4. A portable tube bending device according to claim 1, wherein said elongated flexible connecting means is a chain.

5. A portable tube bending device according to claim I, wherein said first die member has plural tube receiving recesses therein; and

wherein said mounting means supports said first die member for rotary movement in addition to said reciprocable movement to thereby facilitate a positioning of a different tube receiving recess in said space between said ears.

6. A portable tube bending device according to claim 5, wherein said mounting means comprises a wire member slidably engaged with said base member and engaging said first die member to permit a rotational movement about the longitudinal axis thereof.

7. A portable tube bending device according to claim 6, wherein said wire member is generally C-shaped, the spaced legs of said C-shaped wire member being received through openings in the opposite ends of said first die member.

8. A portable tube bending device according to claim 7, wherein said die member has a narrow neck portion less in diameter than the spacing between said ears to facilitate a rotation of said first die member when said narrow neck portion is positioned between said ears.

9. A portable tube bending device according to claim 1, wherein said second die member and said first die member are pivotally secured by a removable pin.

10. A portable tube bending device according to claim 1, wherein said tube has means defining a flare on opposite ends and at least one fitting nut mounted on said tube between the ends thereof; and

wherein said first die member includes means defining a notch opening outward toward said tube located in said first and second tube receiving recesses and adapted to receive said fitting nut therein to facilitate a bending of said tube closely adjacent one of said ends. 

1. A portable tube bending device, comprising: a base member having a bifurcate end portion defined by a pair of coextensive and laterally spaced ears; an elongated first die member having a first tube receiving recess therein extending parallel to the longitudinal axis thereof and having a diameter equal to the diameter of a tube; mounting means for mounting said first die member on said base member in said space between said ears and adapted to support said first die member for reciprocable movement longitudinally of the longitudinal axis of said die member through said space relative to said base member; a second die member having a curved surface thereon and a second tube receiving recess in said curved surface equal in diameter to said first tube receiving recess, said second die member having first coupling means thereon; pivot support means for pivotally supporting said second die member for movement between said ears, said second die member having a curved surface the radius of which is generally equal to the spacing between said pivot support means and said first die member; means defining an elongated handle and releasable securing means for securing said handle to said second die members; tube gripping means having second coupling means thereon cooperable with said first coupling means to secure said tube gripping means to said second die member; attaching means on said tube gripping means for engaging said tube at a location spaced longitudinally along the axis thereof from the location where said first and second die members engage said tube, said attaching means being adapted to cooperate with a tube having a diameter corresponding to the diameter of said second tube receiving recess whereby a pivoting of said second die member about said pivot support means will effect a bending of a portion of said tube engaged by said tube gripping means relative to a portion of said tube located in said first and second tube receiving recesses; and elongated flexible connecting means having a finite length for connecting said tube gripping means to said second die member so that said second die member and said tube gripping means will remain attached even though said first and second coupling means become uncoupled.
 2. A portable tube bending device according to claim 1, wherein said elongated flexible connecting means is of sufficient length to facilitate a manipulation of said tube gripping means relative to said second die member.
 3. A portable tube bending device according to claim 1, wherein said attaching means on said tube gripping means comprises an elongated pin and means defining a recess therein, both said pin and said recess being positioned to engage a portion of said tube located in said first and second tube receiving recesses whereby a pivoting of said second die member relative to said base member will effect a bending of said tube.
 4. A portable tube bending device according to claim 1, wherein said elongated flexible connecting means is a chain.
 5. A portable tube bending device according to claim 1, wherein said first die member has plural tube receiving recesses therein; and wherein said mounting means supports said first die member for rotary movement in addition to said reciprocable movement to thereby facilitate a positioning of a different tube receiving recess in said space between said ears.
 6. A portable tube bending device according to claim 5, wherein said mounting means comprises a wire member slidably engaged with said base member and engaging said first die member to permit a rotational movement about the longitudinal axis thereof.
 7. A portable tube bending device according to claim 6, wherein said wire member is generally C-shaped, the spaced legs of said C-shaped wire member being received through openings in the opposite ends of said first die member.
 8. A portable tube bending device according to claim 7, wherein said die member has a narrow neck portion less in diameter than the spacing between said ears to facilitate a rotation of said first die member when said narrow neck portion is positioned between said ears.
 9. A portable tube bending device according to claim 1, wherein said second die member and said first die member are pivotally secured by a removable pin.
 10. A portable tube bending device according to claim 1, wherein said tube has means defining a flare on opposite ends and at least one fitting nut mounted on said tube between the ends thereof; and wherein said first die member includes means defining a notch opening outward toward said tube located in said firsT and second tube receiving recesses and adapted to receive said fitting nut therein to facilitate a bending of said tube closely adjacent one of said ends. 